Japan’s Sport Council on Thursday awarded a contract to design and construct a centerpiece, billion-dollar national stadium that forms a key part of Tokyo’s bid to host the 2020 Olympic Games to lauded U.K. firm Zaha Hadid Architects.

It’s also a structure that will take on considerable symbolic importance for Japan: It will be built on the site of the stadium that played a key part in the hosting of the Olympics in Tokyo in 1964, a landmark of the country’s post-World War II recovery that is due to be knocked down to make way for the new stadium in 2015.

The design of the stadium, to be built in time to host the 2019 Rugby World Cup, already awarded to Japan, echoes Ms. Hadid’s signature flowing and futuristic style, most recently seen worldwide in the Aquatics Centre built for the London 2012 Olympics.

She is also the visionary behind buildings like the Guangzhou Opera House in China and MAXXI, the National Museum of 21st Century Arts, in Rome and the Bridge Pavilion in Zaragoza, Spain which have received critical acclaim.

The judges, led by celebrated Japanese architect Tadao Ando, were taken by the fluidity and novelty of the design, and how it complements Tokyo’s crowded geographic and cultural landscape.

“The entry’s dynamic and futuristic design embodies the messages Japan would like to convey to the rest of the world,” said Mr. Ando at a press conference on Thursday. The stadium’s retractable roof also makes it easily transformable from a sports venue to a concert venue. Moreover, completing the build within the six-year span in time for the 2019 Rugby World Cup is a realistic goal, the JSC said.

“I have worked in Japan for 30 years. Our three decades of research into Japanese architecture and urbanism is evident in our winning design and we greatly look forward to building the new National Stadium,” said Ms. Hadid in a statement released Thursday. “The design is both light and cohesive, seamlessly connecting the stadium’s different elements to create a silhouette that integrates with the city.”

The runners-up were designs submitted by Alastair Ray Richardson of the Australian firm Cox Architecture Pty. Ltd. and Japan’s Kazuyo Sejima of SANAA and Nikken Sekkei Ltd.

Mr. Ando said that the final three’s designs had consistently received top marks from the jury since they began deliberations on the 46 submissions received.

The competition jury had laid down firm demands for contestants: The stadium design had to be able to seat 80,000 people; have a retractable able roof; be environmentally efficient; complement the surrounding landscape; allow for smooth traffic; and, finally, be up and ready to host the 2019 Rugby World Cup.

For that tall order, the construction budget is ¥130 billion ($1.62 billion). Ms. Hadid’s firm itself will receive ¥20 million in prize money.

Going forward, according to the JSC timeline, the design plans should be finalized by March 2015. The stadium built for the 1964 games — now used for sports events like soccer matches — will be destroyed by October 2015.

UPDATE:This article was updated at 10 a.m. on Nov. 16 to include comments from Zaha Hadid.

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